Sept. 19, 2012 -- An experimental pill is showing promise for the treatment of
multiple sclerosis.

In two late-phase studies appearing in The New England Journal of Medicine, the drug BG-12 (dimethyl fumarate) reduced relapses by about half in patients with the most common form of MS.

If approved by the FDA, BG-12, which is being developed by drug maker Biogen Idec, will become the third oral drug for people with multiple sclerosis.

The second -- Sanofi Aventis' pill Aubagio -- won FDA approval just last week.

"This is an exciting time in the development of new drugs for MS, especially considering the fact that we had no effective treatments just a few decades ago," says National MS Society Chief Research Officer Timothy Coetzee, PhD.

BG-12 Reduced Relapses, Lesions

Multiple sclerosis is a chronic disease in which the immune system attacks the insulation that coats and protects nerve fibers of the brain and spinal cord.

With the most common type, people experience sporadic attacks or flare-ups of symptoms that are then followed by periods of remission. Symptoms include numbness, fatigue, vision problems, spasms, and issues with bladder and bowel control.

People with this "relapsing-remitting" form of MS were the target group for the new oral drug.

The two newly published trials were funded by the drug's manufacturer.

In one, patients with relapsing-remitting disease who took BG-12 twice a day had a 44% reduction in relapses over two years of treatment. In the second study, the relapse reduction over the same period was 53%.

The most common side effects associated with treatment were flushing and stomach issues such as diarrhea and abdominal pain. But most patients experienced fewer of these events after the first month of treatment.

Twice-daily treatment was also linked to a 71% reduction in new brain lesions associated with MS in one of the studies, led by neurologist Robert J. Fox, MD, who runs the Cleveland Clinic Mellen Center for Multiple Sclerosis.

Fox has served as a paid Biogen Idec consultant for projects unrelated to the BG-12 study.

"In my opinion, BG-12 offers a very strong combination of (effectiveness), safety, and tolerability," he says.

Coetzee says it remains to be seen if the new oral drugs will replace standard first-line injectable treatments.

"My guess is that the injectables will remain an important treatment option," he says. "The more options we have the better."

That's because some people do not respond to certain treatments or cannot tolerate them.

Earlier this year, Biogen filed a request with the FDA to market BG-12 in the U.S. A spokeswoman for the company says the agency could rule on the request by the end of the year.